Field of the Invention
The present invention relates to an apparatus which receives a request for starting communication from another apparatus.
Description of the Related Art
Some printers or projectors include a processing unit which performs print processing or projection processing, and a communication unit which communicates with another communication apparatus. In such a printer or projector (hereinafter, referred to as a communication apparatus), there is a technology in which the processing unit is turned off while the communication unit is turned on so as to be in a power saving state in order to reduce power consumption of the communication apparatus.
In such a communication apparatus, if the communication apparatus receives a request packet for starting communication from another communication apparatus in a power saving state, the communication apparatus transmits a response to the request packet for starting communication to start communication, and both of the processing unit and the communication unit shift to a normal state where the power is on (US Unexamined Publication No. 2007/0162777). The request packet for starting communication refers to, for example, a synchronize (SYN) packet in a transmission control protocol (TCP). Further, if the processing unit shifts from a power-off state to a power-on state, the processing unit performs initialization.
When the communication apparatus shifts from a power saving state to a normal state and the processing unit performs initialization, a communication setting such as an address of the communication apparatus is changed in some cases. If the communication setting has been changed, the communication apparatus cannot communicate with another communication apparatus using the communication setting before the change.
Therefore, there is a problem that, if the communication apparatus transmits a response to a request packet for starting communication which was received in a power saving state even though the communication setting has been changed, the requesting communication apparatus may erroneously recognize that it may communicate with the responding communication apparatus using the communication setting before the change.